> there are already a number of well-done "write your own mini-Scheme" books out there

Point taken, but a Perl implementation has an advantage over C for understanding an implementation because it's much higher level, and over Scheme because there's no incestuous metacircular evaluation to confuse things.

Secondly, yes, you hit the nail on the head about syntax because the Parsing section would use the existing evaluator as a target with new, alternative and interesting syntax, certainly better than those "Pratt parsers" that I've seen. Syntax aesthetics is often ignored in hard CS texts.

Finally the third section on compilation would generate Parrot, making the use of Perl in the other sections doubly relevant, but I said that already.